Policy determination system, policy determination method, and non-transitory computer-readable medium

ABSTRACT

A policy determination system ( 500 ) according to an aspect of the present invention is arranged in a core network ( 10 ) and capable of communicating with a control apparatus ( 100 ) arranged in a radio access network ( 20 ). The control apparatus ( 100 ) is configured to perform control related to a state transition between a CONNECTED state and an IDLE state of a mobile terminal ( 300 ) based on a state control policy supplied from the policy determination system. The policy determination system ( 500 ) includes a policy determination unit ( 502 ) that determines a state control policy according to a situation of the mobile terminal ( 300 ), and a notification unit ( 503  or  205 ) that notifies the control apparatus ( 100 ) of the state control policy. This enables, for example, to reduce the number of signalings which are caused due to repetition of state transition (CONNECTED-IDLE transition) of the mobile terminal and are to be processed by the core network, based on the determination by the core network.

TECHNICAL FIELD

The present invention relates to a mobile communications system that hasbeen studied in the 3GPP (3rd Generation Partnership Project), 3GPP2,WiMAX Forum, and the like, and more particularly, relates to a methodfor controlling a state transition of a mobile terminal between aCONNECTED state and an IDLE state.

BACKGROUND ART

FIG. 4 is a block diagram showing a general configuration example of amobile communications system. In FIG. 4, nodes having nothing to do withthe Background Art section, and nodes unnecessary for explanation areomitted. In FIG. 4, a core network 10 is managed by an operator thatmainly provides mobile communication services. The core network 10 is,for example, a packet switching network (EPC (Evolved Packet Core)) ofan EPS (Evolved Packet System) or a packet switching core network of aUNITS (Universal Mode Telecommunications System) of the 3GPP, a packetswitching core network of CDMA2000 of the 3GGP2, or a packet switchingcore network of a CSN (Connectivity Service Network) of the WiMAX Forum.

A radio access network 20 includes a radio base station 910 and a mobileterminal 930. The radio base station 910 has a function of connecting tothe mobile terminal 930 by a radio access technique. The core network 10includes a mobility management node 200. The mobility management node920 performs mobility management and authentication (security control)of the terminal 930 during radio access, and manages setting processesand control signals for a user data transfer path between the corenetwork 10 and the radio base station 910. The mobile terminal 930 has aradio interface, and connects to the radio base station 910 by the radioaccess technique and also connects to the core network 10.

In the EPS of the 3GPP, the radio base station 910 corresponds to an eNB(Enhanced NodeB); the mobility management node 920 corresponds to an MME(Mobility Management Entity); and the mobile terminal 930 corresponds toa UE (User Equipment). As the radio access technique, LTE (Long TermEvolution) is employed.

In the UMTS of the 3GPP, the radio base station 910 corresponds tofunctions of an RNC (Radio Network Controller) and an NB (NodeB). Themobility management node 200 corresponds to an SGSN (Serving GPRSSupport Node), and the mobile terminal 300 corresponds to the UE (UserEquipment). As the radio access technique, W-CDMA (Wideband CodeDivision Multiple Access) is employed.

In the CDMA2000 system of the 3GGP2, the radio base station 100corresponds to a BS (Base Station); the mobility management node 200corresponds to a PDNS (Packet Data Serving Node); and the mobileterminal 300 corresponds to an MS (Mobile Station). As the radio accesstechnique, EV-DO (Evolution-Data Optimized) is employed.

In a communication system of the WiMAX Forum, the radio base station 100corresponds to functions of an ASN-GW (Access Service Network Gateway)and the BS (Base Station). The mobility management node 200 correspondsto an HA (Home Agent), and the mobile terminal 300 corresponds to an MS(Mobile Station). As the radio access technique, WiMAX is employed.

Aspects and embodiments of the present invention herein described arenot dependent on architectures of mobile communications systems.Accordingly, aspects and embodiments of the present invention can beapplied to mobile communications systems standardized in the 3GPP,3GPP2, and WiMAX Forum. However, the following description will be madewith reference to the mobile communications system of the EPS in the3GPP so as to describe configurations and operations according toaspects and embodiments of the present invention in detail.

In FIG. 33, a radio control including allocation of resources (channels)in a radio section between the mobile terminal 930 and the radio basestation 910 is carried out in an RRC (Radio Resource Control) layer, andexchange of control messages and packet communication between the mobileterminal 300 and the core network 10, for example, are carried out in aNAS (Non-Access Stratum) layer which is upper layer of the RRC.

In RRC layer, there are two states of RRC_IDLE and RRC_CONNECTED. In theRRC_CONNECTED state, the radio base station 910 holds information (i.e.,RRC context) on an RRC connection between the mobile terminal 930 andthe radio base station 910, and transmission and reception of user datain the radio section between the mobile terminal 930 and the radio basestation 910 are thereby enabled. On the other hand, in the RRC_IDLEstate, the radio base station 100 releases the information (RRC context)on the RRC connection of the mobile terminal 300, discontinuousreception (DRX) that is configured by NAS is indicated to the mobileterminal 300, and therefore the mobile terminal 300 is able to receive apaging signal.

During the discontinuous reception, a radio communication unit includedin the mobile terminal 930 is activated to perform a reception operationin accordance with time slots to be received by the mobile terminal 930.During the other time periods, the radio communication unit is broughtinto a standby state (power-off). Thus, the discontinuous receptionprovides a great effect of power saving in the mobile terminal 930.

In the NAS layer, there are two states of ECM (EPS ConnectionManagement)_IDLE and ECM_CONNECTED. In the ECM-CONNECTED state, a NASconnection is established between the mobile terminal 930 and themobility management node 920. The mobility management node 920accurately recognizes the position of the mobile terminal 930 (i.e.,recognizes a radio base station to which the mobile terminal isconnected) by using the NAS connection, and performs a handover processwhen the mobile terminal 930 moves between base stations. On the otherhand, the ECM_IDLE state is a state in which the NAS connection is notestablished between the mobile terminal 930 and the mobility managementnode 920. In the ECM_IDLE state, the mobility management node 920performs mobility management of the mobile terminal 930 in units oftracking areas that each includes a plurality of radio base stations.Accordingly, even when the mobile terminal 930 in the ECM_IDLE statemoves between radio base stations, no handover process occurs. When themobile terminal 930 returns to the ECM_CONNECTED state from the ECM_IDLEstate, the mobile terminal 930 needs to be synchronized with the corenetwork 10 (i.e., needs to perform location registration).

When the mobile terminal 930 is in ECM_IDLE state and the mobilitymanagement node 920 performs the mobility management of the mobileterminal 930 in units of tracking areas, there is no need to perform thehandover process even when the mobile terminal 930 moves between radiobase stations. This provides an advantage of reducing a load on the corenetwork (including the mobility management node 200).

It can be said that the states (CONNECTED or IDLE) related toconnections of the RRC layer and the NAS layer are synchronized. This isbecause it is necessary to establish a connection in the RRC layer (comeinto the RRC_CONNECTED state) so as to establish a connection in the NASlayer (come into the ECM_CONNECTED state), and the connection in the NASlayer is established simultaneously with the establishment of theconnection in the RRC layer. This is also because when the connection inone of the RRC layer and the NAS layer is released (transits to the IDLEstate), the connection in the other layer is also released (transits tothe IDLE state).

When the NAS layer transits from the ECM_CONNECTED state to the ECM_IDLEstate, an S1 Release Procedure is executed. As an example of a triggerfor executing the S1 Release Procedure is a release of RRC-connection (atransition to RRC_IDLE state). When the S1 Release Procedure is executedin the state where the connection in the RRC layer is established (RRCCONNECTION state), the connection in the RRC layer is also released(transits to RRC_IDLE). That is, when the RRC layer and the NAS layertransit to the IDLE state, the S1 Release Procedure is executed.

On the other hand, when the RRC layer and the NAS layer transit to theCONNECTED state from the IDLE state, a Service Request Procedure isexecuted. When the Service Request Procedure is executed, the NASconnection and the RRC connection are established.

Here, the definition of terms “CONNECTED state” and “IDLE state” whichare used in this specification and the claims is described. The term“IDLE state” refers to a state in which a mobile terminal does notperform signaling for session management and mobility management with acore network, and radio resources in a radio access network such asE-UTRAN are released, as in the case of the ECM_IDLE state and theRRC_IDLE state of the 3GPP described above. On the other hand, the term“CONNECTED state” refers to a state in which radio resources for sendingand receiving control signals (control messages) for session managementand mobility management between at least a mobile terminal and a corenetwork are secured in a radio access network, and the control signals(control messages) can be sent and received between the mobile terminaland the core network, as in the case of the ECM_CONNECTED state and theRRC_CONNECTED state of the 3GPP described above. That is, it is onlynecessary that the “CONNECTED state” is be a state in which a mobileterminal is connected to a core network so as to enable transmission andreception of control signals (control messages) for at least sessionmanagement and mobility management. In other words, the “CONNECTEDstate” does not require a state in which a bearer for transferring userdata between a mobile terminal and an external packet data network (PDN)is established.

CITATION LIST Non Patent Literature

-   Non Patent Literature 1: 3GPP TS 23.401 V10.0.0 (2010-06), “General    Packet Radio Service (GPRS) enhancements for Evolved Universal    Terrestrial Radio Access Network (E-UTRAN) access (Release 10)”,    Section 4.6.3, Section 5.3.4, and Section 5.3.5, June, 2010-   Non Patent Literature 2: 3GPP TS 36.331 V9.1.0 (2009-12), “Evolved    Universal Terrestrial Radio Access (E-UTRA) Radio Resource Control    (RRC); Protocol specification (Release 9)”, Section 4.2.1, Section    5.3.8, and Section 5.3.9, January, 2010-   Non Patent Literature 3: 3GPP TS 24.301 V9.1.0 (2009-12),    “Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS);    Stage 3”, Section 5.3.1.2, December, 2009

SUMMARY OF INVENTION Technical Problem

As described in the Background Art section, when the radio connection ofthe mobile terminal 930 is released (transits to RRC_IDLE) in a radioresource management layer between the mobile terminal 930 and the radiobase station 910, the S1 Release Procedure for releasing the connectionof the upper layer (NAS layer) is executed as well. Also when the RRClayer transits from the RRC_IDLE state to the RRC_CONNECTED state, theService Request Procedure for establishing the connection of the upperlayer (NAS layer) is executed as well. Upon execution of the S1 ReleaseProcedure or the Service Request Procedure, a plurality of signalings isexchanged between the mobile terminal 930 and the core network 10.

Many of recent mobile terminals including smartphones, which placeimportance on power saving, operate to release a radio connectionimmediately when there is no communication, and to cause the state ofeach of the radio resource management layer and the upper layer totransit to the IDLE state. Meanwhile, as a tendency for applicationprograms that run on a mobile terminal, the number of applicationprograms that periodically connects with a server to send and receiveinformation is increasing. As a result, the recent mobile terminalsoperate to transit to the IDLE state immediately after completion ofcommunication and then transit to the CONNECTED state immediately for anapplication that periodically performs communication. That is, thephenomenon in which a mobile terminal repeatedly transits between theIDLE state and the CONNECTED state occurs in many cases. This causes aproblem that the number of signalings to be processed by the corenetwork 10 increases, resulting in an increase in load on the corenetwork 10.

As a method for reducing the number of signalings caused due torepetition of the state transition of the mobile terminal 930, it ispossible to execute control for adjusting a timing of the transitionfrom the CONNECTED state to the IDLE state in the mobile terminal 930.If the state transition of the mobile terminal 930 can be optimized, areduction in the number of signalings caused due to repetition of statetransition can be expected. However, in the present specifications formobile communications systems, such as the 3GPP, it is impossible forthe core network 10 (for example, the mobility management node 920) tocontrol the timing of the state transition of the mobile terminal 930between the CONNECTED state and the IDLE state (hereinafter referred toas “CONNECTED-IDLE transition”). On the other hand, when a statetransition request arrives from the mobile terminal 930, the corenetwork 10 accepts the state transition request. That is, there is aproblem that it is impossible for the core network 10 to proactively(i.e., based on the determination by the core network 10) performcontrol related to the CONNECTED-IDLE transition of the mobile terminal930, such as control for changing a time interval for the mobileterminal 930 to transit from the CONNECTED state to the IDLE state, orcontrol for blocking the state transition request from the mobileterminal 930, for example. In other words, there is a problem that thecore network 10 cannot control the timing of the CONNECTED-IDLEtransition of the mobile terminal 930.

It is an object of the present invention to provide a policydetermination system, a policy determination method, and a program,which contribute to reducing, based on the determination by the corenetwork 10, the number of signaling which are caused due to repetitionof the state transition of the mobile terminal 930 (i.e., CONNECTED-IDLEtransition) and are to be processed by the core network 10.

Solution to Problem

A first aspect of the present invention includes a policy determinationsystem. The policy determination system is arranged in a core networkand is capable of communicating with a control apparatus arranged in aradio access network including a radio base station. The controlapparatus is configured to perform control related to a state transitionbetween a CONNECTED state and an IDLE state of a mobile terminalconnected to the radio base station, based on a control policy suppliedfrom the policy determination system. The policy determination systemincludes: a policy determination unit that determines the control policyaccording to a situation of the mobile terminal; and a notification unitthat notifies the control apparatus of the control policy.

A second aspect of the present invention includes a policy determinationmethod. The policy determination method is carried out by a policydetermination system that is arranged in a core network and is capableof communicating with a control apparatus arranged in a radio accessnetwork including a radio base station. The control apparatus isconfigured to perform control related to a state transition between aCONNECTED STATE and an IDLE state of a mobile terminal connected to theradio base station, based on a control policy supplied from the policydetermination system. The policy determination method according to thisaspect includes: determining the control policy according to a situationof the mobile terminal; and notifying the first control node of thecontrol policy.

A third aspect of the present invention is a program for causing acomputer to execute the method according to the above-described secondaspect of the present invention.

Advantageous Effects of Invention

According to the above-described aspects of the present invention, it ispossible to provide a policy determination system, a policydetermination method, and a program, which contribute to reducing thenumber of signalings which are caused due to repetition of a statetransition of a mobile terminal (i.e., CONNECTED-IDLE transition) andare to be processed by the core network, based on the determination bythe core network.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a configuration example of a mobilecommunications system in a first embodiment;

FIG. 2 is a diagram showing a configuration example of a mobilitymanagement node according to the first embodiment;

FIG. 3 is a table showing an example of a state control policy accordingto the first embodiment;

FIG. 4 is a diagram showing a configuration example of a radio basestation according to the first embodiment;

FIG. 5 is a sequence diagram showing a flow of processes in which themobility management node requests the radio base station to perform astate control of a mobile terminal in the first embodiment;

FIG. 6 is a flowchart showing an operation example when the mobilitymanagement node transmits a state control request in the firstembodiment;

FIG. 7 is a flowchart showing an operation example when the radio basestation executes the state control for the mobile terminal in the firstembodiment;

FIG. 8 is a diagram showing a configuration example of a mobilitymanagement node in a second embodiment;

FIG. 9 is a diagram showing a configuration example of a radio basestation in the second embodiment;

FIG. 10 is a table showing an example of a state control policy in thesecond embodiment;

FIG. 11 is a flowchart showing a processing example when the radio basestation receives a state control request from the mobility managementnode in the second embodiment;

FIG. 12 is a diagram showing a configuration example of a mobilitymanagement node in a third embodiment;

FIG. 13 is a diagram showing a configuration example of a radio basestation in the third embodiment;

FIG. 14 is a table showing an example of a state control policy in thethird embodiment;

FIG. 15 is a flowchart showing a processing example when the radio basestation receives a state control request from the mobility, managementnode in the third embodiment;

FIG. 16 is a diagram showing a configuration example of a mobilitymanagement node in a fourth embodiment;

FIG. 17 is a sequence diagram showing a flow of processes to start astate control for a mobile terminal when the mobile terminal startsconnection and handover to a radio base station;

FIG. 18 is a flowchart showing a processing example when the mobilitymanagement node receives a connection notification of the mobileterminal from the radio base station in the fourth embodiment;

FIG. 19 is a diagram showing a configuration example of a mobilecommunications system in a fifth embodiment;

FIG. 20 is a diagram showing a configuration example of a mobilitymanagement node in the fifth embodiment;

FIG. 21 is a table showing an example of a state control policy in thefifth embodiment;

FIG. 22 is a sequence diagram showing a flow of processes when themobility management node determines a state control for a specificmobile terminal in the fifth embodiment;

FIG. 23 is a flowchart showing a processing example when the mobilitymanagement node starts the state control for the specific mobileterminal in the fifth embodiment;

FIG. 24 is a diagram showing a configuration example of a mobilecommunications system in a sixth embodiment;

FIG. 25 is a diagram showing a configuration example of a policydetermination node in the sixth embodiment;

FIG. 26 is a flowchart showing a processing example when the policydetermination node determines and notifies the state control policy in asituation of a mobile terminal in the sixth embodiment;

FIG. 27 is a table showing a first example of a rule that defines arelationship between situations of mobile terminal and state controlpolicies in the sixth embodiment;

FIG. 28 is a table showing a second example of a rule that defines arelationship between situations of mobile terminal and state controlpolicies in the sixth embodiment;

FIG. 29 is a table showing a third example of a rule that defines arelationship between situations of mobile terminal and state controlpolicies in the sixth embodiment;

FIG. 30 is a diagram showing a configuration example of a mobilitymanagement node in a seventh embodiment;

FIG. 31 is a diagram showing a configuration example of a radio basestation in the seventh embodiment;

FIG. 32 is a table showing an example of a state control policy in theseventh embodiment; and

FIG. 33 is a diagram showing a configuration example of a mobilecommunications system according to a background art.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments to which the present invention is applied willbe described in detail with reference to the drawings. In the drawings,identical or corresponding elements are denoted by the same referencenumerals, and a redundant explanation thereof is omitted as appropriatefor clarification of the explanation.

First Embodiment

FIG. 1 is a block diagram showing a configuration example of a mobilecommunications system according to this embodiment. The system shown inFIG. 1 includes a mobility management node 20 arranged in a core network10, a radio base station 100, and a mobile terminal 300. An arrangementand basic functions and operations of the mobility management node 200,the radio base station 100, and the mobile terminal 300 are similar tothose of the mobility management node 920, the radio base station 910,and the mobile terminal 930 which are shown in FIG. 33.

The mobility management node 200 is configured to be able to acquire apolicy related to control for CONNECTED-IDLE transition of the mobileterminal 300. Control for states of the mobile terminal 300 includingcontrol for CONNECTED-IDLE transition is hereinafter referred to as“state control”. Policies related to “state control” for the mobileterminal 300 are referred to as “a state control policy”. The statecontrol policy is individually determined for each mobile terminal 300.The state control policy may be managed by the mobility management node200 itself, or may be managed by another node that is accessible fromthe mobility management node 200. The state control policy is used tocontrol the adjustment of a timing of a state transition of the mobileterminal 300 between a CONNECTED state and an IDLE state. The statecontrol policy includes, for example, at least one of designation of atime interval in which the mobile terminal 300 transits from theCONNECTED state to the IDLE state (hereinafter referred to as “IDLEtransition interval”) and designation as to whether or not to block astate transition request from the mobile terminal 300 or an O&M server.

Further, the mobility management node 200 is configured to be able todetermine a terminal as a state control target from among a plurality ofmobile terminals 300 connected to a plurality of radio base stations 100under management of the mobility management node 200. A number ofvariations of the method for determining a control target terminal andof the timing of the determination can be made. Specific examples of themethod for determining a control target terminal and the timing of thedetermination will be described in detail in second and subsequentembodiments described later. For example, the mobility management node200 may determine a control target terminal according to a load statusof signaling of the core network 10.

The mobility management node 200 notifies the radio base station 100, towhich the terminal 300 is connected, of the state control policy appliedto the terminal 300 which is determined as the control target. Thenotification of the state control policy to the base station 100 may beperformed by sending, from the mobility management node 200 to the basestation 100, a state control request message that includes a terminal IDof the terminal 300 determined as the control target and the statecontrol policy, for example.

The radio base station 100 is configured to be able to receive, from themobility management node 200, the terminal ID, which allowsidentification of the terminal 300 determined as the control target, andthe state control policy. Based on the received state control policy,the radio base station 100 performs a state control (i.e., control forCONNECTED-IDLE transition) for the terminal 300 determined as thecontrol target. As a specific example, the base station 100 may changethe “IDLE transition interval” which is applied to the mobile terminal300 determined as the control target. Further, the base station 100 maystart blocking of the state transition request having arrived from themobile terminal 300 determined as the control target.

According to the mobility management node 200 and the radio base station100 of this embodiment, the core network 10 can proactively control thetiming of the CONNECTED-IDLE transition of the mobile terminal 300 basedon the determination by the core network 10 (i.e., the mobilitymanagement node 200). Accordingly, the number of signalings which arecaused due to repetition of the CONNECTED-IDLE transition of the mobileterminal 300 and which are to be processed by the core network 10 can bereduced based on the determination by the core network 10.

The configuration and operation of the mobility management node 200 andthe radio base station 100 in this embodiment will be described below.FIG. 2 is a block diagram showing a configuration example of themobility management node 200. The mobility management node 200 shown inFIG. 2 includes an interface 201, a control determination unit 202, aterminal management unit 203, a policy management unit 204, and a policynotification unit 205. Note that FIG. 2 shows components in a majorportion necessary for explanation of this embodiment, and theillustration of the other portion is omitted.

The interface 201 is an interface available for communication with theradio base station 100. The interface 201 is used for transmission andreception of control signals (messages) related to the state control ofthe mobile terminal 300.

The control determination unit 202 determines a mobile terminal as astate control target from among the plurality of mobile terminals 300connected to the plurality of radio base stations 100. Further, thecontrol determination unit 202 acquires a control policy correspondingto the control target terminal from the policy management unit 204, andnotifies the radio base station 100, to which the control targetterminal is connected, of the terminal ID of the control target terminaland the control policy applied thereto. The terminal ID herein describedis an ID that allows unique identification of the mobile terminal 300 onthe mobile communications system. Specific examples of the ID includeIMSI (International Mobile Subscriber Identity), IMEI (InternationalMobile Equipment Identity), and GUTI (Globally Unique Temporary ID). Thecontrol determination unit 202 may acquire the terminal ID of theterminal in the case of determining the control target terminal.

A number of variations of the method for specifying the control targetterminal by the control determination unit 202 can be made. Further, anumber of variations of the timing of determining the control targetterminal can be made as follows. That is, for example, the control isstarted at the timing when a mobile terminal has just connected, or thecommunication characteristics of the mobile terminal are monitored andthe control is started for the mobile terminal that satisfies a certaincondition. A specific method for specifying the control target terminalwill be described in the second and subsequent embodiments.

The terminal management unit 203 is a function unit that performsmobility management of the mobile terminal 300, and recognizes themobile terminals 300 that have connected (attached) to a plurality ofradio base stations 100. Upon receiving, from the control determinationunit 202 using the terminal ID of the control target terminal, aninquiry as to the base station 10 to which the control target terminalhas connected, the terminal management unit 203 notifies the controldetermination unit 202 of the base station ID of the radio base station100 to which the mobile terminal 300 corresponding to the terminal ID iscurrently connected.

The policy management unit 204 stores the state control policy relatedto the state transition of the mobile terminal 300. The state transitionpolicy in this embodiment is recorded for each mobile terminal, andincludes a description of the IDLE transition interval of the mobileterminal 300. FIG. 3 shows an example of the state control policymanaged by the policy management unit 204. In the example of FIG. 3, theterminal ID of the control target terminal is configured as a primarykey, and the state control policy corresponding to the primary key ismanaged. In the example of FIG. 3, the IDLE transition interval isregistered as a state control policy.

Upon acquiring, from the control determination unit 202, the terminal IDof the control target terminal, the state control policy to be appliedto the control target terminal, and the base station ID of the radiobase station 100 to which the control target terminal is currentlyconnected, the policy notification unit 205 sends a state controlrequest to the radio base station 100 corresponding to the base stationID. The state control request includes the terminal ID of the controltarget terminal and the state control policy.

FIG. 4 is a block diagram showing a configuration example of the radiobase station 100 in this embodiment. The radio base station 100 shown inFIG. 4 includes a core-side interface 101, a radio interface 102, astate control unit 103, a monitoring unit 104, a timer function unit105, and an IDLE transition start unit 106. Note that FIG. 4 showscomponents in a major portion necessary for explanation of thisembodiment, and the illustration of the other portion is omitted.

The core-side interface 101 is an interface available for communicationwith the mobility management node 200 arranged in the core network 10.The interface 101 is used for reception of the state control requestfrom the mobility management node 200, and for transmission of aresponse to the mobility management node 200.

The radio interface 102 is an interface for performing radiocommunication between the radio base station 100 and the mobile terminal300.

The state control unit 103 receives the state control request sent fromthe mobility management node 200 via the core-side interface 101.Further, the state control unit 103 has a function of executing a statecontrol (control for CONNECTED-IDLE transition) for the control targetterminal by activating the monitoring unit 104, the timer function unit105, and the IDLE transition start unit 106 based on the terminal ID andthe state control policy which are included in the state controlrequest. The state control operation performed by the base station 100including the operation of the state control unit 103 will be describedin detail later.

The monitoring unit 104 has a function of monitoring a communicationstate of a monitoring target terminal (i.e., monitoring whether totransmit or receive data). The monitoring unit 104 receives, from thestate control unit 103, the terminal ID of the mobile terminal 300 asthe monitoring target, and monitors the communication state of themobile terminal 300 corresponding to the received terminal ID. Afterconfirming the state in which the monitoring target terminal is notperforming data communication, the monitoring unit 104 notifies thestate control unit 103 of the terminal ID and information indicating thestate in which data communication is not performed. Further, afterconfirming that data communication is resumed from the state in whichthe monitoring target terminal is not performing data communication, themonitoring unit 104 notifies the state control unit 103 of the terminalID and information indicating that data communication is resumed.

The timer function unit 105 has a function of measuring the IDLEtransition interval for each mobile terminal. Upon receiving, from thestate control unit 103, the terminal ID of the mobile terminal 300 to bemeasured and the IDLE transition interval, the timer function unit 105secures a timer for the mobile terminal corresponding to the acquiredterminal ID in a memory. This terminal ID is the terminal ID of thecontrol target terminal which is notified from the mobility managementnode 200. This IDLE transition interval is the IDLE transition intervalincluded in the state control policy notified from the mobilitymanagement node 200. Further, upon receiving a timer start requestincluding the terminal ID from the state control unit 103, the timerfunction unit 105 starts a measurement using the timer for the mobileterminal corresponding to the terminal ID. Then, when the timer for themobile terminal reaches the configured IDLE transition interval, thetimer function unit 105 sends to the state control unit 103 anexpiration notification including the terminal ID of the mobile terminalafter expiration of the interval.

Upon receiving the IDLE transition start request including the terminalID from the state control unit 103, the IDLE transition start unit 106starts a process for causing the mobile terminal 300 corresponding tothe received terminal ID to transit from the CONNECTED state to the IDLEstate. A specific example of the process for causing the mobile terminal300 to transit from the CONNECTED state to the IDLE state is S1 RELEASEPROCEDURE.

Subsequently, a flow of processes in which the mobility management node200 requests the radio base station 100 to perform the state control ofthe mobile terminal 300 will be described with reference to the sequencediagram of FIG. 5.

First, in step S100, the mobility management node 200 determines amobile terminal as a state control target, acquires a state controlpolicy to be applied to the control target terminal, and specifies theradio base station 200 to which the control target terminal hasconnected.

In step S101, the mobility management node 200 sends, to the radio basestation 100 to which the control target terminal has attached, the statecontrol request including the terminal ID of the control target terminaland the state control policy to be applied to the control targetterminal.

In step S102, the radio base station 100 starts the state control basedon the terminal ID and the state control policy which are received fromthe mobility management node 200.

In step S103, the radio base station 100 notifies the mobilitymanagement node 200 of a state control response indicating that theexecution of the control is started.

Referring next to the flowchart of FIG. 6, an operation example when themobility management node 200 sends the state control request to theradio base station 100 will be described. First, in step S200, thecontrol determination unit 202 determines the start of the state controlfor a specific mobile terminal (i.e., control target terminal). Thecontrol determination unit 202 acquires the terminal ID of the controltarget terminal according to the determination of the control targetterminal. In step S201, the control determination unit 202 acquires,from the policy management unit 204, the state control policycorresponding to the terminal ID of the control target terminal.

In step S202, the control determination unit 202 sends an inquiry to theterminal management unit 203 by using the terminal ID of the controltarget terminal, thereby receiving the base station ID of the radio basestation 100 to which the control target terminal is currently connected.In step S203, the control determination unit 202 notifies the policynotification unit 205 of the terminal ID of the control target terminal,the state control policy, and the base station ID of the radio basestation to which the control target terminal has connected. The policynotification unit 205 sends, to the radio base station 100 correspondingto the base station ID, the state control request including the terminalID and the control policy which are received from the controldetermination unit 202.

Referring next to the flowchart of FIG. 7, an operation example when theradio base station 300 executes the state control for the mobileterminal 100 will be described. First, in step S300, the state controlunit 103 receives the state control request via the core-side interface101. In step S301, the state control unit 103 acquires, from the statecontrol request, the terminal ID of the control target terminal and theIDLE transition interval, which is a parameter within the state controlpolicy, and sets the terminal ID and the IDLE transition interval to thetimer function unit 105.

In step S302, the state control unit 103 notifies the monitoring unit104 of the terminal ID of the control target terminal which is obtainedfrom the state control request. The monitoring unit 104 startsmonitoring the data communication of the mobile terminal 300corresponding to the notified terminal ID. In step S303, afterconfirming the state in which the monitoring target terminal is notperforming data communication, the monitoring unit 104 notifies thestate control unit 103 of the terminal ID of this mobile terminal.

In step S304, the state control unit 103 notifies the timer functionunit 105 of the timer start request as well as the terminal ID includedin the notification received from the monitoring unit 104 in step S303.The timer function unit 105 starts counting the IDLE transition intervalconfigured in step S301 with respect to the terminal ID designated bythe timer start request.

In step S305, the state control unit 103 monitors whether to receivefrom the monitoring unit 104 a notification indicating that the datacommunication of the mobile terminal determined as a counting target isresumed before the count of the timer function unit 105, which isstarted in step S304, reaches the IDLE transition interval. When thedata communication is not resumed before the count of the timer functionunit 105 reaches the IDLE transition interval, the process proceeds toS306. When the data communication is resumed, the process proceeds toS307.

In step S306, the timer function unit 105 stops the timer when the countstarted in step S304 reaches the IDLE transition interval, and sends tothe state control unit 103 a notification indicating that the configuredtime interval is expired, as well as the terminal ID of the mobileterminal of the counting target.

In step S307, upon confirming that the data communication of the mobileterminal of the counting target is resumed, the monitoring unit 104notifies the state control unit 103 of the terminal ID of the mobileterminal and a notification indicating resuming of data communication.Upon receiving the notification from the monitoring unit 104, the statecontrol unit 103 notifies the timer function unit 105 of the targetterminal ID and a notification indicating that the count time of thetimer is reset. The timer function unit 105 resets the count time of thetimer corresponding to the received terminal ID.

In step S308, upon receiving the notification indicating that theconfigured time interval is expired in step S307 from the timer functionunit 105, the state control unit 103 sends to the IDLE transition startunit 106 the terminal ID notified from the timer function unit 105. TheIDLE transition start unit 106 starts a process for causing the mobileterminal 300 corresponding to the terminal ID received from the statecontrol unit 103 to transit from the CONNECTED state to the IDLE state(i.e., IDLE transition process).

After starting the IDLE transition control in step S308, the basestation 100 of this embodiment may repeatedly perform the step S302 andsubsequent steps shown in FIG. 3, when the terminal 300 which has beencaused to transit to the IDLE state transits to the CONNECTED stateagain.

According to the specific example described in this embodiment, the timeperiod in which the mobile terminal 300 transits from the CONNECTEDstate to the IDLE state (i.e., IDLE transition interval) can beconfigured for each mobile terminal 300 from the mobility managementnode 200 arranged in the core network 10.

Second Embodiment

This embodiment illustrates a modification of a specific example (thatis, IDLE transition interval) of parameters designated by the statecontrol policy described in the first embodiment. Specifically, in thisembodiment, in addition to the IDLE transition interval of the mobileterminal 300, a policy for blocking a request or an event that triggerstransition of the mobile terminal 300 from the CONNECTED state to theIDLE state is added as one of the parameters of the state controlpolicy.

FIG. 8 is a block diagram showing a configuration example of themobility management node 200 in this embodiment. In the example of FIG.8, parameters included in the state control policy which is held in apolicy management unit 204B are partially different from the parametersof the state control policy which is held in the policy management unit204 shown in FIG. 2. The other elements shown in FIG. 8 are similar tothe corresponding elements of FIG. 2.

FIG. 9 is a block diagram showing a configuration example of the radiobase station 100 in this embodiment. As compared with the configurationexample shown in FIG. 4, a block unit 107 is added in the example ofFIG. 9. The functions of a state control unit 103B shown in FIG. 9 arepartially different from the functions of the state control unit 103shown in FIG. 4. The other elements shown in FIG. 9 are similar to thecorresponding elements of FIG. 4.

The policy management unit 204B of the mobility management node 200stores the state control policy including a policy for blocking arequest or an event that triggers transition of the mobile terminal 300to the IDLE state (referred to as a block policy), as well as the IDLEtransition interval of the mobile terminal 300. FIG. 10 shows a specificexample of the state control policy managed by the policy managementunit 204B. Examples of the block policy include an IDLE transitionrequest (e.g., request for transition to RRC_IDLE) received from themobile terminal 300, and an IDLE transition request received from an O&M(Operations & Maintenance) server.

The state control unit 103B of the radio base station has the functionsof the state control unit 103 described above with reference to FIG. 4.Further, upon receiving the state control request from the mobilitymanagement node 200, the state control unit 103B notifies the block unit107 of the terminal ID and the block policy within the state controlpolicy contained in the received request.

The block unit 107 of the radio base station 100 blocks a request or anevent that triggers transition of the mobile terminal 300 correspondingto the terminal ID to the IDLE state, based on the terminal ID and theblock policy which are notified from the state control unit 103B. The“blocking” includes “ignoring” a request or an event that triggerstransition to the IDLE state, and also includes inhibiting execution ofthe IDLE transition process to be carried out according to the requestor the event. The block unit 107 is able to block based on the blockpolicy for each mobile terminal 300. Upon receiving a block startrequest from the state control unit 103B, the block unit 107 starts ablock operation.

Referring next to the flowchart of FIG. 11, the operation of the radiobase station 100 of this embodiment will be described. FIG. 11 shows aprocess example when the radio base station 100 receives the statecontrol request from the mobility management node 200 via the core-sideinterface 101. Here, steps different from those shown in FIG. 7described above will be focused and described, and the description ofthe same steps as those shown in FIG. 7 is omitted.

In step S400, the state control unit 103B acquires the terminal ID andthe block policy within the state control policy from the received statecontrol request, and sets the terminal ID and the block policy to theblock unit 107.

In step S401, the state control unit 103B notifies the block unit 107 ofthe block start request and the terminal ID included in the notificationreceived from the monitoring unit 104 in step S303. The block unit 107starts the block operation for the mobile terminal 300 corresponding tothe notified terminal ID based on the block policy set in step S400.

In step S402, upon receiving the notification, which indicates that theconfigured time is expired and includes the terminal ID, from the timerfunction unit 105 in step S306, the state control unit 103B sends ablock stop request including this terminal ID to the block unit 107. Theblock unit 107 receives the block stop request, and then stops the blockoperation for the mobile terminal 300 corresponding to the terminal IDincluded in the stop request.

In step S403, upon receiving, from the monitoring unit 104, the terminalID and the notification indicating that the data communication of themobile terminal 300 of the monitoring target is resumed in step S305,the state control unit 103B sends the block stop request including thisterminal ID to the block unit 107. The block unit 107 receives the blockstop request, and then stops the block operation for the mobile terminal300 corresponding to the terminal ID included in the stop request.

According to the specific example described in this embodiment, it ispossible to obtain the effect of the specific example described in thefirst embodiment, and it is also possible to cause the radio basestation 100 to perform the operation for blocking a request or an eventthat triggers transition of the mobile terminal 300 from the CONNECTEDstate to the IDLE state, based on an instruction from the core network10 (specifically, the mobility management node 200). For example, arequest for transition from the CONNECTED state to the IDLE state, whichreaches the radio base station 100 from the mobile terminal 300, can beblocked for a certain period of time.

Third Embodiment

This embodiment illustrates an example in which the core network 10notifies the radio base station 100 of a policy related to control of aradio resource when the mobile terminal 300 in the CONNECTED state isnot performing data communication (hereinafter referred to as “radiocontrol policy”), as well as the state control policy described in thefirst embodiment.

FIG. 12 is a block diagram showing a configuration example of themobility management node 200 in this embodiment. In the example of FIG.12, parameters included in the state control policy held in a policymanagement unit 204C are partially different from the parameters of thestate control policy held in the policy management unit 204 shown inFIG. 2. The other elements shown in FIG. 12 are similar to thecorresponding elements of FIG. 2.

FIG. 13 is a block diagram showing a configuration example of the radiobase station 100 in this embodiment. As compared with the configurationexample shown in FIG. 4, a radio control unit 108 is added in theexample of FIG. 13. The functions of the state control unit 103C shownin FIG. 13 are partially different from the functions of the statecontrol unit 103 shown in FIG. 4. The other components shown in FIG. 13are similar to the corresponding elements of FIG. 4.

The policy management unit 204C of the mobility management node 200stores the above-mentioned “radio control policy”, i.e., the policyrelated to control of a radio resource when the mobile terminal in theCONNECTED state is not performing data communication, as well as thepolicy for performing control for the CONNECTED-IDLE transition (forexample, the IDLE transition interval of the mobile terminal 300, andthe block policy). FIG. 14 shows a specific example of the state controlpolicies managed by the policy management unit 204C. In the example ofFIG. 14, the radio control policy is added as one of the state controlpolicies. An example of the radio control policy is an interval ofdiscontinuous reception (DRX) of the mobile terminal 300 in theCONNECTED state.

The state control unit 130C of the radio base station 100 has thefunctions of the state control unit 103 described above with referenceto FIG. 4. Further, the state control unit 103C has the function ofnotifying the radio control unit 108 of the terminal ID included in therequest and the radio control policy within the state control policy,upon receiving the state control request from the mobility managementnode 200.

According to the terminal ID and the radio control policy which arenotified from the state control unit 103C, the radio control unit 108 ofthe radio base station 100 performs the radio resource control(specifically, setting of DRX) of the mobile terminal 300 correspondingto the notified terminal ID. The radio control unit 108 controls theradio resource based on the radio control policy for each mobileterminal 300. The discontinuous reception (DRX) in the case where themobile terminal 300 is in the CONNECTED state (i.e., RRC_CNNECTED state)can be controlled. For example, it is proposed that the base station 100configures the discontinuous reception (DRX) while observing an activityof the mobile terminal 300 (Reference: 3GPP TS 36.300 “Evolved UniversalTerrestrial Radio Access (E-UTRA) And Evolved Universal TerrestrialRadio Access Network (E-UTRAN); Overall Description”).

Next, the operation of the radio base station 100 of this embodimentwill be described with reference to the flowchart of FIG. 15. FIG. 15shows a process to be carried out when the radio base station 100receives the state control request from the mobility management node 200via the core-side interface 101. Here, steps different from those shownin FIG. 7 described above are focused and described, and the descriptionof the same steps as those shown in FIG. 7 is omitted.

In step S500, the state control unit 103C acquires the terminal ID andthe radio control policy within the state control policy from thereceived state control request, and sets the terminal ID and the radiocontrol policy to the radio control unit 108.

In step S501, the state control unit 103C notifies the radio controlunit 108 of the radio control start request and the terminal ID includedin the notification received from the monitoring unit 104 in step S303.The radio control unit 108 starts the radio control (setting of DRXvalue) for the mobile terminal 300 corresponding to the notifiedterminal ID based on the radio control policy (DRX value) configured instep S500.

Next, in step S502, upon receiving the notification, which indicatesthat the configured time is expired and includes the terminal ID, fromthe timer function unit 105 in step S306, the state control unit 103Csends a radio control stop request including the terminal ID to theradio control unit 108. The radio control unit 108 receives the radiocontrol stop request, and then stops the radio control for the mobileterminal 300 corresponding to the terminal ID included in the stoprequest.

Next, in step S503, upon acquiring, from the monitoring unit 104, theterminal ID and the notification indicating that the data communicationof the mobile terminal 300 of the monitoring target is resumed in stepS305 of the first embodiment, the state control unit 103C sends theradio control stop request including this terminal ID to the radiocontrol unit 108. The radio control unit 108 having received the radiocontrol stop request stops the radio control for the mobile terminal 300corresponding to the terminal ID included in the stop request. If theDRX is deactivated at the timing of step S503, this process is ignored.

According to the specific example described in this embodiment, it ispossible to obtain the effect of the specific example described in thefirst embodiment, and it is also possible to perform, for the radio basestation 100, the setting for handling the radio resource related to themobile terminal 300 maintained in the CONNECTED state, based on aninstruction from the core network 10 (specifically, the mobilitymanagement node 200). For example, the interval of the DRX by the mobileterminal 300 in the case where there is no data communication in theCONNECTED state can be configured to the radio base station 100 from thecore network 10 for each mobile terminal 300.

Fourth Embodiment

In this embodiment, a specific example of the timing of determining aterminal to be subjected to a state control (i.e., control targetterminal) will be described. Specifically, in this embodiment, thecontrol target terminal is determined at the timing when the mobileterminal 300 connects (i.e., cell selection, cell reselection) orperforms handover to the radio base station 100 under management of themobility management node 200.

FIG. 16 is a block diagram showing a configuration example of themobility management node 200 in this embodiment. In the example of FIG.16, the functions of a control determination unit 202D and a terminalmanagement unit 203D are partially different from the functions of thecontrol determination unit 202 and the terminal management unit 203which are described above with reference to FIG. 2. The other elementsshown in FIG. 16 are similar to the corresponding elements of FIG. 2.

The terminal management unit 203D of the mobility management node 200has the functions of the terminal management unit 203 described abovewith reference to FIG. 2. Further, when the mobile terminal 300 connects(i.e., cell selection, cell reselection) or performs handover to theradio base station 100, the terminal management unit 203D sends, to thecontrol determination unit 202D, a “connection notification” includingthe terminal ID of the mobile terminal 300 and the base station ID ofradio base station 100 to which the mobile terminal 300 is connected.

The control determination unit 202D of the mobility management node 200has the functions of the control determination unit 202 described abovewith reference to FIG. 2. Further, upon receiving a connectionnotification indicating the connection of the mobile terminal 300 fromthe terminal management unit 203D, the control determination unit 202Dconfirms whether the new terminal 300 is a control target terminal.Then, when the new terminal 300 is judged as the control targetterminal, the control determination unit 202D requests the radio basestation 100 to perform the state control of the terminal.

Referring next to the sequence diagram of FIG. 17, a description will bemade of a flow of processes for starting the state control for themobile terminal upon being triggered by the connection or handover tothe radio base station 100 of the mobile terminal 300. In step S600, themobile terminal 300 starts a connection process or a handover processfor the radio base station 100. At the time of starting this process,the mobile terminal 300 notifies the radio base station 100 of theterminal ID. Next, in step S601, the radio base station 100 transfers aconnection request or a handover request received in step S600 to themobility management node 200. In step S602, based on the terminal IDcontained in the connection request or the handover request received instep S601, the mobility management node 200 checks whether the mobileterminal corresponding to the terminal ID is a control target terminal.That is, the connection request or the handover request sent from theradio base station 100 to the mobility management node 200 correspondsto the “connection notification”. In step S603, when the checked mobileterminal is judged as the control target as a result of checking in stepS602, the mobility management node 200 determines to start the statecontrol for the mobile terminal. The subsequent procedure may be similarto step S101 and subsequent steps shown in FIG. 5.

Referring next to the flowchart of FIG. 18, the operation of themobility management node 200 of this embodiment will be described. FIG.18 shows a process to be carried out when the mobility management node200 receives the connection notification of the mobile terminal from theradio base station 100. Here, steps different from those shown in FIG. 6described above are focused and described, and the description of thesame steps as those shown in FIG. 6 is omitted.

In step S700, the terminal management unit 203D receives from the radiobase station 100 the connection notification including the terminal IDof the terminal 300 which is attempting to connect or to performhandover to the radio base station 100, and notifies the controldetermination unit 202D of the terminal ID. Specific examples of theconnection notification include a connection request and a handoverrequest of the mobile terminal 300.

In step S701, the control determination unit 202D confirms whether thestate control policy corresponding to the terminal ID acquired in stepS700 exists in the policy management unit 204. When the state controlpolicy does not exist, it is judged that the mobile terminal 300corresponding to the terminal ID is not the control target, and thecontrol process is completed. On the other hand, when the state controlpolicy exists (YES in step S701), the process proceeds to step S201which is described above with reference to FIG. 6.

According to the specific example described in this embodiment, it ispossible to check whether the mobile terminal 300 is a terminal to besubjected to the state control including the control for theCONNECTED-IDLE transition, at the timing when the mobile terminal 300connects or performs handover to the radio base station 100 undermanagement of the mobility management node 200, thereby making itpossible to start the state control if the terminal is the controltarget terminal.

Fifth Embodiment

In this embodiment, a modification of a specific example of thearrangement of the state control policy described in the firstembodiment will be described. Specifically, while FIG. 2 illustrates theconfiguration in which the mobility management node 200 includes thepolicy management unit 204, this embodiment illustrates an example inwhich the policy management unit is arranged outside the mobilitymanagement node 200.

FIG. 19 is a block diagram showing a configuration example of the mobilecommunications system according to this embodiment. As compared with theexample of FIG. 1, a subscriber server 400 is newly added in the exampleof FIG. 19. The subscriber server 400 manages subscriber information andcorresponds to an HSS (Home Subscriber Server) in the 3GPP. Thesubscriber server 400 of this embodiment is characterized by managingthe state control policy for each user. FIG. 21 shows an example of thestate control policy managed by the subscriber server 400. In theexample of FIG. 21, the state control policy is managed as a piece ofinformation that is managed for each subscriber, by using a subscriberID for identifying each subscriber as a key.

FIG. 20 is a block diagram showing a configuration example of themobility management node 200 of this embodiment. In the example of FIG.20, the policy management unit 204 is omitted from the configurationexample shown in FIG. 2 and a subscriber server interface 206 is added.The functions of a control determination unit 202E are partiallydifferent from the functions of the control determination unit 202 shownin FIG. 2. The other elements shown in FIG. 20 are similar to thecorresponding elements of FIG. 2.

The subscriber server interface 206 of the mobility management node 200is an interface that enables exchange of the subscriber information,which includes the state control policy, between the mobility managementnode 200 and the subscriber server 400. The control determination unit202E of the mobility management node 200 has the functions of thecontrol determination unit 202 described above with reference to FIG. 2.Further, when determining the state control for the mobile terminal 300,the control determination unit 202E sends an inquiry to the subscriberserver 400 by using the subscriber ID of the control target terminal,thereby acquiring the state control policy corresponding to the controltarget terminal.

Referring next to the sequence diagram of FIG. 22, a description will bemade of a flow of processes, in the mobile communications system shownin FIG. 19, for acquiring the state control policy corresponding to thecontrol target terminal from the subscriber server 400 when the mobilitymanagement node 200 determines the control target terminal to besubjected to the state control. First, in step S800, the mobilitymanagement node 200 determines the state control for a certain mobileterminal, and recognizes the subscriber ID of the control targetterminal. In step S801, the mobility management node 200 sends, to thesubscriber server 400, a control policy request including the subscriberID of the control target terminal. In step S802, the subscriber server400 acquires, from the subscriber information managed by the subscriberserver 400, the state control policy corresponding to the subscriber IDcontained in the control policy request acquired in step S801. Then, thesubscriber server 400 returns, to the mobility management node 200, acontrol policy response including the subscriber ID corresponding to theacquired state control policy. In step S803, the mobility managementnode 200 sends, to the radio base station 100, the state control requestincluding the state control policy acquired in step S802, therebyrequesting the radio base station 100 to perform the state controlincluding the control for the CONNECTED-IDLE transition for the controltarget terminal. The procedure of step S802 and subsequent steps may besimilar to step S101 and subsequent steps shown in FIG. 5.

Referring next to the flowchart of FIG. 23, the operation of themobility management node 200 of this embodiment will be described. FIG.23 shows a process to be carried out when the mobility management node200 starts the state control for the mobile terminal 300. Here, step 900which is a difference from FIG. 6 described above is focused anddescribed, and the description of steps S200, S202, and S203, which arethe same as those of FIG. 6, is omitted. In step S900, the controldetermination unit 202E sends a request for the state control policy tothe subscriber server 400 by using the terminal ID (subscriber ID inthis case) of the control target terminal, and acquires the statecontrol policy corresponding to the terminal ID (subscriber ID) from thesubscriber server 400.

According to the specific example described in this embodiment, thestate control policy related to the control for the CONNECTED-IDLEtransition of the mobile terminal are registered as a part of thesubscriber information in the subscriber server 400 for each subscriber,thereby enabling the state control for each subscriber.

Sixth Embodiment

In this embodiment, a specific example of the method for determining aterminal to be subjected to a state control (i.e., control targetterminal) and a specific example of the method for determining a statecontrol policy will be described. Specifically, in this embodiment, asituation of the mobile terminal 300 is obtained, and the mobileterminal 300 to be subjected to the state control and the state controlpolicy to be applied to the terminal are determined according to the“situation of the mobile terminal 300”. The “situation of the mobileterminal 300”, which is used to determine the state control policy, isan element for determining a control content related to theCONNECTED-IDLE transition of the mobile terminal 300. Examples of thesituation of the mobile terminal 300 include: (1) a communicationfrequency of the mobile terminal 300; (2) a movement frequency of themobile terminal 300; (3) an external network (connection destinationnetwork) to which the mobile terminal 300 is connected; (4) a time zone(behavior pattern) to which the mobile terminal 300 belongs; (5) alocation where the mobile terminal 300 is positioned; (6) an applicationprogram currently activated in the mobile terminal 300; (7) a batteryremaining amount of the mobile terminal 300; (8) a radio access network(wireless LAN, LTE, WiMAX, etc.) to which the mobile terminal 300 iscurrently connected; and (9) an arbitrary combination thereof. Since thesituation of the mobile terminal 300 as described above is not fixed butvaried, the state control policy to be applied is changed according to achange in the situation of the mobile terminal 300 in this embodiment.

FIG. 24 is a block diagram showing a configuration example of the mobilecommunications system according to this embodiment. As compared with theexample of FIG. 1, a policy determination node 500 is newly added in theexample of FIG. 24. The policy determination node 500 acquires thesituation of the mobile terminal 300 and determines the state controlpolicy to be applied based on the situation of the mobile terminal 300.In the example of FIG. 24, the policy determination node 500 isdescribed as another node which is independent of the mobilitymanagement node 200. However, the arrangement of the functions of thepolicy determination node 500 is appropriately determined based on thedesign concept of the network architecture. For example, the functionsof the policy determination node 500 may be arranged in the mobilitymanagement node 200 or the radio base station 100.

Next, the configuration of the policy determination node 500 will bedescribed. FIG. 2 is a block diagram showing a configuration example ofthe policy determination node 500 of this embodiment. The policydetermination node 500 shown in FIG. 25 includes a terminal situationrecognition unit 501, a policy determination unit 502, and a policynotification unit 503. Note that FIG. 25 shows components in a majorportion necessary for explanation of this embodiment, and theillustration of the other portion is omitted.

The terminal situation recognition unit 501 recognizes the situation ofthe mobile terminal 300 which is used to determine the state controlpolicy to be applied to the mobile terminal 300. The terminal situationrecognition unit 501 may recognize the situation of the mobile terminal300 by monitoring/measuring the mobile terminal 300 by itself, or mayrecognize the situation of the mobile terminal 300 by acquiringinformation indicating the situation of the mobile terminal 300 fromanother node such as the mobility management node 200 or the radio basestation 100.

The policy determination unit 502 determines the state control policy tobe applied to the mobile terminal 300 according to the situation of themobile terminal 300 which is acquired by the terminal situationrecognition unit 501. The policy determination unit 502 may determinethe state control policy to be applied to the mobile terminal 300 byusing a rule that defines the correspondence between the situation ofthe mobile terminal 300 and the state control policy. In the case ofusing a numerical parameter as the situation of the mobile terminal 300,such as a movement frequency or a communication frequency, the policydetermination unit 502 may determine the parameter of the state controlpolicy by performing a calculation using this numerical parameter. As aspecific example, the policy determination unit 502 may calculate thevalue of the IDLE transition interval by using the value of the movementfrequency or the communication frequency.

The policy notification unit 503 notifies the mobility management node200, which manages the mobile terminal 300 to which the state controlpolicy is applied (i.e., the control target terminal), of the statecontrol policy determined by the policy determination unit 502. When thefunctions of the policy determination node 500 are arranged in themobility management node 200, the policy notification unit 503 notifiesthe radio base station 100 of the state control policy determined by thepolicy determination unit 502.

Next, the operation of the policy determination node 500 of thisembodiment will be described with reference to the flowchart of FIG. 26.FIG. 26 shows a processing example when the policy determination node500 recognizes the situation of the mobile terminal 300. In step S2001,the terminal situation recognition unit 501 recognizes the situation ofthe mobile terminal 300. In step S2002, the policy determination unit502 determines whether the state control policy corresponding to thesituation of the mobile terminal 300 which is acquired in step S2001exits, based on the rule that defines the correspondence between thesituation of the mobile terminal 300 and the state control policy. Whenthe state control policy corresponding to the situation of the mobileterminal 300 which is acquired in step S2001 is not predetermined, thepolicy determination unit 502 determines “error” or “no need for statecontrol” and aborts the process. In step S2003, the policy notificationunit 503 notifies the mobility management node 200 which manages thecontrol target terminal, or the radio base station 100 to which thecontrol target terminal is currently connected, of the state controlpolicy determined in step S2002.

As described above, specific examples of the situation of the mobileterminal 300 which is recognized by the policy determination node 500include an external network to which the mobile terminal 300 isconnected, a movement frequency, a communication frequency, a locationof the mobile terminal 300, and a radio access network to which themobile terminal 300 is currently connected. The method for recognizingthe situation of the mobile terminal 300 is different depending on whichparameter is used to indicate the situation of the mobile terminal 300.Some specific examples of the method for recognizing the situation ofthe mobile terminal 300 will be described in detail below.

First Example: Movement Frequency and Communication Frequency of MobileTerminal

In the second example, the policy determination node 500 recognizes themovement frequency and the communication frequency of the mobileterminal 300 as the situation of the mobile terminal 300. The movementfrequency of the mobile terminal 300 indicates the number of times ofmovement of the mobile terminal 300 between radio base stations per unittime. The communication frequency of the mobile terminal 300 indicatesthe number of times of communication of the mobile terminal 300 per unittime. For example, the terminal situation recognition unit 501 mayreceive a notification as to detection results of a movement or aninitiation of communication of the mobile terminal 300 from a node, suchas the mobility management node 200, which is capable of detecting themovement or the initiation of communication of the mobile terminal 300.In this case, the terminal situation recognition unit 501 may count thenotifications as to the movement or the initiation of communication ofthe mobile terminal 300, to thereby calculate the movement frequency andthe communication frequency per unit time. Further, the terminalsituation recognition unit 501 may receive a notification containingmeasurement results of the movement frequency and the communicationfrequency of the mobile terminal 300 per unit time from a node, such asthe mobility management node 200, which is capable of detecting themovement and the initiation of communication of the mobile terminal 300.

The policy determination unit 502 determines the state control policy tobe applied to the terminal, based on the rule that defines thecorrespondence between the movement frequency and communicationfrequency of the mobile terminal 300 and the state control policy. FIG.27 shows an example of the rule that defines the correspondence betweenthe movement frequency and communication frequency of the mobileterminal 300 and the state control policy. In the example of FIG. 27,the state control policy to be applied to the terminal is switcheddepending on whether the movement frequency per unit time (for example,10 minutes or one hour) of the mobile terminal 300 is equal to or morethan the communication frequency.

The policy notification unit 503 notifies the mobility management node200, which manages the mobile terminal 300, of the determined statecontrol policy as well as the identifier of the mobile terminal 300.Note that when the functions of the policy determination node 500 arearranged in the mobility management node 200, the state control for themobile terminal can be started at the time when the mobility managementnode 200 measures the movement frequency and the communication frequencyof the mobile terminal 300 per unit time.

According to this specific example, the usage circumstances (movementand communication interval) of the mobile terminal 300 are monitored tothereby determine the state control policy so as to reduce the number ofsignalings to be processed by the core network 10, according to a changein the usage circumstances of the mobile terminal 300. Note that thepolicy determination node 500 may determine the state control policysuch that a transition interval from the CONNECTED state to the IDLEstate is relatively longer in the case where the movement frequency ofthe mobile terminal 300 is equal to or more than the communicationfrequency, than that in the case where the movement frequency of themobile terminal 300 is less than the communication frequency.

Second Example: Connection Destination Network of Mobile Terminal

In the first example, the policy determination node 500 recognizes anexternal network (connection destination network) to which the mobileterminal 300 is connected, as the situation of the mobile terminal 300.In the case of 3GPP, the connection destination network is referred toas PDN (Packet Data Network) and is identified by APN (Access PointName). The terminal situation recognition unit 501 acquires information(e.g., APN) on the connection destination network of the mobile terminal300. The terminal situation recognition unit 501 may acquire theinformation on the connection destination network from the mobilitymanagement node 200. The mobility, management node 200 acquires the APNas a piece of subscriber information by sending an inquiry to the HSS(Home Subscriber Server), and then performs signaling with packettransfer nodes, such as P-GW (PDN-Gateway) and S-GW (Serving Gateway),so as to establish a connection (bearer) between the mobile terminal 300and the external network (PDN). Accordingly, the mobility managementnode 200 recognizes the information (APN) on the connection destinationnetwork of the mobile terminal 300 under management. For example, themobility management node 200 may notify the policy determination node500 of the information (APN) on the connection destination network uponbeing triggered by the connection of the mobile terminal 300 to theconnection destination network.

The policy determination unit 502 determines the state control policybased on the rule that defines the correspondence between the connectiondestination network and the state control policy. FIG. 28 shows anexample of the rule that defines the correspondence between theconnection destination network and the state control policy.

The policy notification unit 503 notifies the mobility management node200, which manages the mobile terminal 300, of the determined statecontrol policy as well as the identifier of the mobile terminal 300.When the functions of the policy determination node 500 are arranged inthe mobility management node 200, the state control for the terminal canbe started at the time when the mobility management node 200 recognizesthe connection destination network of the mobile terminal 300.

According to this specific example, for example, the utilizationcharacteristics (movement frequency and communication interval) of themobile terminal 300 can be estimated based on the connection destinationnetwork of the mobile terminal 300. This enables determination of thestate control policy so as to reduce the number of signalings to beprocessed by the core network 10, by determining the state controlpolicy according to the connection destination network of the mobileterminal 300, without directly measuring the utilization characteristicsof the mobile terminal 300.

For example, in the case of connecting the mobile terminal 300 to asales management system of a vending machine manufacturer, this mobileterminal 300 is assumed as a terminal that is embedded in a vendingmachine with a small degree of movement. Accordingly, the policydetermination node 500 may determine the state control policy, such thatthe transition interval from the CONNECTED state to the IDLE state isincreased according to the values of the movement frequency and thecommunication interval of vending machines which are observed in advanceor determined in advance. Further, in the case of connecting the mobileterminal 300 to a traffic management system of a traffic informationmanagement company, this mobile terminal 300 is assumed as a terminalthat is embedded in an automobile, a two-wheel vehicle, or the like witha large degree of movement. Accordingly, the policy determination node500 may determine the state control policy such that the transitioninterval from the CONNECTED state to the IDLE state is shortenedaccording to the values of the movement frequency and the communicationinterval of automobiles, two-wheel vehicles, or the like which areobserved in advance or determined in advance.

Third Example: Time Zone (Behavior Pattern) of Mobile Terminal

In the third example, the policy determination node 500 recognizes atime zone of the mobile terminal 300 as the situation of the mobileterminal 300. The terminal state recognition unit 501 may check the timeas needed, and may detect a change from a first time zone (firstbehavior pattern) to a second time zone (second behavior pattern), thefirst time zone and the second time zone being pre-defined for themobile terminal 300.

The policy determination unit 502 determines the state control policy tobe applied to the terminal, based on the rule that defines thecorrespondence between a plurality of time zones, which are pre-definedfor the mobile terminal 300, and the state control policies. FIG. 30shows an example of the rule that defines the correspondence between theplurality of time zones, which are pre-defined for the mobile terminal300, and the state control policies. In the example of FIG. 30, aplurality of time zones is defined for the mobile terminal 300 (e.g.,terminal A, terminal B) or a terminal group (e.g., group C) including atleast one mobile terminal 300. As for the terminal A, for example, thestate control policy is switched between the first time period from 8o'clock to 19 o'clock (i.e., daytime) and the second time zone from 19o'clock to 8 o'clock (i.e., nighttime).

The policy notification unit 503 notifies the mobility management node200, which manages the mobile terminal 300, of the determined statecontrol policy as well as the identifier of the mobile terminal 300.When the functions of the policy determination node 500 are arranged inthe mobility management node 200, the state control for the terminal canbe started at the time when the first time zone (first behavior pattern)leaves and the second time zone (second behavior pattern) comes.

According to this specific example, the utilization characteristics(movement frequency and communication interval) of the mobile terminal300 can be estimated based on the behavior pattern of the user of themobile terminal 300. This enables determination of the state controlpolicy so as to reduce the number of signalings to be processed by thecore network 10, by determining the state control policy according tothe time zone in which the behavior pattern of the user is different,without directly measuring the utilization characteristics of the mobileterminal 300. During the nighttime, for example, it is estimated thatthe user sleeps and does not move. Accordingly, the policy determinationnode 500 may determine the state control policy such that the transitioninterval from the CONNECTED state to the IDLE state of the mobileterminal 300 is relatively longer in the nighttime than that in thedaytime.

Fourth Example: Location where Mobile Terminal is Positioned

The terminal situation recognition unit 501 of the policy determinationnode 500 recognizes a location where the mobile terminal 300 ispositioned, as the situation of the mobile terminal 300. The policydetermination unit 502 determines the state control policy to be appliedto the mobile terminal, based on the rule that defines thecorrespondence between the state control policy and the location wherethe mobile terminal 300 is positioned.

According to this specific example, the utilization characteristics(movement frequency and communication interval) of the mobile terminal300 can be estimated based on the location where the mobile terminal 300exists. This enables determination of the state control policy so as toreduce the number of signalings to be processed by the core network 10,by determining the state control policy according to the location of themobile terminal 300, without directly measuring the utilizationcharacteristics of the mobile terminal 300. For example, when the mobileterminal 300 is located in the home of the user of the mobile terminal300, it is estimated that the mobile terminal 300 is less likely tomove. Accordingly, the policy determination node 500 may determine thestate control policy such that the transition interval from theCONNECTED state to the IDLE state is relatively longer when the mobileterminal is located in the home of the user of the mobile terminal 300,than that when the mobile terminal 300 is not located in the home.

Fifth Example: Application Program Activated by Mobile Terminal

The terminal situation recognition unit 501 of the policy determinationnode 500 recognizes an application program currently activated in themobile terminal 300, as the situation of the mobile terminal 300. Thepolicy determination unit 502 determines the state control policy to beapplied to the terminal, based on the rule that defines thecorrespondence between the application program activated in the mobileterminal 300 and the state control policy.

According to this specific example, the utilization characteristics(movement frequency and communication interval) of the mobile terminal300 can be estimated based on the application program currentlyactivated in the mobile terminal 300. This enables determination of thestate control policy so as to reduce the number of signalings to beprocessed by the core network 10, by determining the state controlpolicy according to the application program currently activated in themobile terminal 300, without directly measuring the utilizationcharacteristics of the mobile terminal 300. For example, when anapplication program for establishing communication with a mobileterminal once every three minutes is activated, it is estimated that thecommunication frequency of the mobile terminal 300 is high. Accordingly,the policy determination node 500 may determine the state control policysuch that the transition interval from the CONNECTED state to the IDLEstate is relatively longer than that when this application program isnot activated.

Six Example: Battery Remaining Amount of Mobile Terminal

The terminal situation recognition unit 501 of the policy determinationnode 500 recognizes a battery remaining amount of the mobile terminal300 as the situation of the mobile terminal 300. The policydetermination unit 502 determines the state control policy to be appliedto the terminal, based on the rule that defines the correspondencebetween the battery remaining amount of the mobile terminal 300 and thestate control policy. Alternatively, the policy determination unit 502may determine the IDLE transition interval, which is included in thestate control policy, by performing a calculation using the value of thebattery remaining amount.

Seventh Example: Radio Access Network to which Mobile Terminal isConnected

The terminal status recognition unit 501 of the policy determinationnode 500 recognizes a radio access network to which the mobile terminal300 is connected, as the status of the mobile terminal 300. The policydetermination unit 502 determines the state control policy to be appliedto the terminal, based on the rule that defines the correspondencebetween the state control policy and the radio access network (wirelessLAN, LTE, WiMAX, etc.) to which the mobile terminal 300 is connected.

According to this specific example, the utilization characteristics(movement frequency and communication interval) of the mobile terminal300 can be estimated based on the type of the radio access network usedby the mobile terminal 300. This enables determination of the statecontrol policy so as to reduce the number of signalings to be processedby the core network 10, by determining the state control policyaccording to the radio access network used by the mobile terminal 300,without directly measuring the utilization characteristics of the mobileterminal 300. For example, when the mobile terminal 300 is connected toa wireless LAN service of a hotel, it is estimated that the terminal isless likely to move. Accordingly, in this case, the policy determinationnode 500 may determine the state control policy such that the transitioninterval from the CONNECTED state to the IDLE state is relatively longerthan that when the mobile terminal 300 is connected to a microcell basestation of a cellular phone carrier.

According to the specific examples described in this embodiment, theindividual state control policies are prepared for a plurality ofsituations of the mobile terminal 300, and the situation of the mobileterminal 300 is monitored, which enables switching of the state controlpolicy to be applied according to the situation of the mobile terminal300. This makes it possible to control the CONNECTED-IDLE transitionaccording to the situation of the mobile terminal 300.

Seventh Embodiment

In this embodiment, a modification of a specific example (that is, IDLEtransition interval) of parameters designated by the state controlpolicies described in the first embodiment will be described.Specifically, in this embodiment, instead of the IDLE transitioninterval of the mobile terminal 300, a policy for blocking a request oran event that triggers transition of the mobile terminal 300 from theCONNECTED state to the IDLE state is used as a parameter of the statecontrol policy.

FIG. 30 is a block diagram showing a configuration example of themobility management node 200 in this embodiment. In the example of FIG.30, the functions of a control determination unit 202H are partiallydifferent from the functions of the policy management unit 204 shown inFIG. 2. The types of policies recorded in a policy management unit 204Hare partially different from those of the policy management unit 204shown in FIG. 2. In the example of FIG. 30, a block start notificationunit 209 is added instead of the policy notification unit 205, and ablock stop notification unit 210 is also added. The other elements shownin FIG. 30 are similar to the corresponding elements of FIG. 2.

FIG. 31 is a block diagram showing a configuration example of the radiobase station 100 in this embodiment. As compared with the example ofFIG. 4, the monitoring unit 104, the timer function unit 105, and theIDLE transition start unit 106 are omitted and a block unit 107H isadded in the example of FIG. 31. The functions of a state control unit103H are partially different from the functions of the state controlunit 103 described above with reference to FIG. 4. The other elementsshown in FIG. 31 are similar to the corresponding elements of FIG. 4.

The policy management unit 204H of the mobility management node 200manages the block policy for each mobile terminal 300. As described inthe second embodiment of the invention, the block policy is a policy forblocking a request or an event that triggers transition of the mobileterminal 300 from the CONNECTED state to the IDLE state. FIG. 32 shows aspecific example of the state control policies of this embodiment whichare managed by the policy management unit 204B. In the example of FIG.32, the terminal ID of the control target terminal is configured as aprimary key, and the block policy corresponding to the primary key ismanaged.

The control determination unit 202H determines the mobile terminal 300on which the block control is imposed from among the mobile terminals300 connected to the radio base station 100 under management of themobility management node 200, acquires the control policy correspondingto the control target terminal from the policy management unit 204H, andnotifies the block start notification unit 209 of the terminal ID of theblock start target terminal and the control policy to be applied.Further, the control determination unit 202H determines the mobileterminal 300 on which the block control is stopped, and notifies theblock stop notification unit 210 of the terminal ID of the mobileterminal 300 on which the block control is stopped.

Upon acquiring, from the control determination unit 202H, the terminalID of the block start target terminal and the state control policy to beapplied, the block start notification unit 209 sends the block startrequest including the terminal ID and the state control policy to theradio base station 100.

Upon acquiring the terminal ID of the block stop target terminal fromthe control determination unit 202H, the block stop notification unit210 sends the block stop request including the terminal ID to the radiobase station 100.

Upon receiving the block start request from the mobility management node200, the state control unit 103H of the radio base station 100 notifiesthe block unit 107H of the terminal ID included in the start request andthe block policy within the state control policy, contained in the startrequest, as the block start request. Further, upon receiving the blockstop request from the mobility management node 200, the state controlunit 103H notifies the block unit 107H of the terminal ID contained inthe received stop request, as the block stop request.

The block unit 107H of the radio base station 100 has the functionssimilar to those of the block unit 107 described above with reference toFIG. 9. Specifically, when the block start request is received from thestate control unit 103H, the block unit 107H starts blocking based onthe terminal ID and the block policy contained in the start request.Further, upon acquiring the block stop request from the state controlunit 103H, the block unit 107H stops blocking with respect to theterminal ID contained in the stop request.

According to the specific example described in this embodiment, it ispossible to cause the radio base station 100 to perform the operationfor blocking a request or an event that triggers transition of themobile terminal 300 from the CONNECTED state to the IDLE state, based onan instruction from the core network 10 (specifically, the mobilitymanagement node 200). In other words, according to the specific exampledescribed in this embodiment, it is possible for the core network 10 toproactively control the timing of the CONNECTED-IDLE transition in themobile terminal 300 based on the determination by the core network 10(i.e., the mobility management node 200). Accordingly, the number ofsignalings which are caused due to repetition of the CONNECTED-IDLEtransition of the mobile terminal 300 and which are to be processed bythe core network 10 can be reduced based on the determination by thecore network 10.

Other Embodiment

Any combination of the specific examples described in the first toseventh embodiments of the invention may be implemented.

The function of the mobility management node 200 serving as “policysupply system” described in the first to seventh embodiments, i.e., “thefunction for supplying the radio access network 20 with the statecontrol policy related to the CONNECTED-IDLE transition of the mobileterminal 300” may be arranged in another node that is arranged in thecore network 10 and is different from the mobility management node.Further, the function of the mobility management node 200 serving as“policy supply system” described in the first to seventh embodiments maybe arranged in a manner distributed to a plurality of nodes in the corenetwork 10. In other words, the arrangement of the function of themobility management node 200 serving as “policy, supply system”described in the first to seventh embodiments is appropriatelydetermined based on the design concept of the network architecture. As aspecific example, in the case of applying the first to seventhembodiments to the UMTS in the 3GPP, the function of the above-mentionedmobility management node 200 serving as “policy, supply system” may bearranged in the GGSN (Gateway GPRS Support Node). Furthermore, thefunction of the mobility management node 200 described in the first toseventh embodiments may be arranged in the O&M (Operations &Maintenance) server.

The function of the radio base station 100 serving as “a controlapparatus that performs the state control related to the CONNECTED-IDLEtransition of the mobile terminal 300” described in the first to seventhembodiments may be arranged in another node that is different from theradio base station 100. Specifically, the function may be arranged in anode that is arranged in the radio access network 20 and has a radioresource management function. As a specific example, in the case ofapplying the first to seventh embodiments to the UMTS in the 3GPP, thefunction of the above-mentioned radio base station 100 may beimplemented not by the NB (NodeB), but by a modification of schedulingfunction and radio bearer management function of the RNC (Radio NetworkController). In the case of applying this embodiment to a communicationsystem of the WiMAX Forum, the operation of the radio base station 100described above may be implemented not by the BS (Base Station), but bya modification of the functions of the ASN-GW (Access Service NetworkGateway).

The first to seventh embodiments illustrate an example in which thestate control policy is supplied from the core network 10 (typically,the mobility management node 200 or the policy determination node 500)to the radio base station 100, and the radio base station 100 performscontrol for the CONNECTED-IDLE transition of the mobile 300 based on thestate control policy. However, the state control policy determined bythe core network 10 may be supplied to the mobile terminal 300 from thecore network 10. In this case, the mobile terminal 300 may autonomouslycontrol the CONNECTED-IDLE transition of itself according to the statecontrol policy received from the core network 10. That is, the functionof the radio base station 100 serving as “a control apparatus thatperforms a state control related to the CONNECTED-IDLE transition of themobile terminal 300” described in the first to seventh embodiments maybe arranged in the mobile terminal 300 itself. Also such modificationsmake it possible to reduce the number of signalings, which are causeddue to repetition of the state transition (CONNECTED-IDLE transition) ofthe mobile terminal and are to be processed by the core network, basedon the determination by the core network.

The process for requesting the state control to the radio base station100 by the mobility management node 200 and the process for controllingthe CONNECTED-IDLE transition of the mobile terminal 300 based on thestate control policy from the mobility management node 200 by the radiobase station 100, which are described in the first to seventhembodiments, may be implemented using a semiconductor processing devicesuch as an ASIC (Application Specific Integrated Circuit) or a DSP(Digital Signal Processor). These processes may also be implemented bycausing a computer, such as a microprocessor, to execute a program.Specifically, a program including instructions for causing a computer toexecute an algorithm shown in at least one of FIGS. 6, 7, 11, 15, 18,23, and 26 may be prepared and supplied to a computer.

This program can be stored and provided to a computer using any type ofnon-transitory computer readable media. Non-transitory computer readablemedia include any type of tangible storage media. Examples ofnon-transitory computer readable media include magnetic storage media(such as floppy disks, magnetic tapes, hard disk drives, etc.), opticalmagnetic storage media (e.g., magneto-optical disks), CD-ROM (Read OnlyMemory), CD-R, CD-R/W, and semiconductor memories (such as mask ROM,PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (randomaccess memory), etc.). The program may be provided to a computer usingany type of transitory computer readable media. Examples of transitorycomputer readable media include electric signals, optical signals, andelectromagnetic waves. Transitory computer readable media can providethe program to a computer via a wired communication line, such aselectric wires and optical fibers, or a radio communication line.

In addition, the present invention is not limited to the above-describedembodiments, and various modifications can be made without departingfrom the scope of the present invention described above.

This application is based upon and claims the benefit of priority fromJapanese patent application No. 2011-000991, filed on Jan. 6, 2011, thedisclosure of which is incorporated herein in its entirety by reference.

REFERENCE SIGNS LIST

-   10 CORE NETWORK-   20 RADIO ACCESS NETWORK (RADIO ACCESS NETWORK: RAN)-   100 RADIO BASE STATION-   101 CORE-SIDE INTERFACE-   102 RADIO INTERFACE-   103 STATE CONTROL UNIT-   104 MONITORING UNIT-   105 TIMER FUNCTION-   106 IDLE TRANSITION START UNIT-   103B STATE CONTROL UNIT IN SECOND EMBODIMENT-   107 BLOCK UNIT IN SECOND EMBODIMENT-   113C STATE CONTROL UNIT IN THIRD EMBODIMENT-   108 RADIO CONTROL UNIT IN THIRD EMBODIMENT-   103H STATE CONTROL UNIT IN SEVENTH EMBODIMENT-   107H BLOCK UNIT IN SEVENTH EMBODIMENT-   200 MOBILITY MANAGEMENT NODE-   201 INTERFACE-   202 CONTROL DETERMINATION UNIT-   203 TERMINAL MANAGEMENT UNIT-   204 POLICY MANAGEMENT UNIT-   205 POLICY NOTIFICATION UNIT-   204B POLICY MANAGEMENT UNIT IN SECOND EMBODIMENT-   204C POLICY MANAGEMENT UNIT IN THIRD EMBODIMENT-   202D CONTROL DETERMINATION UNIT IN FOURTH EMBODIMENT-   203D TERMINAL MANAGEMENT UNIT IN FOURTH EMBODIMENT-   204C CONTROL DETERMINATION UNIT IN FIFTH EMBODIMENT-   206 SUBSCRIBER SERVER INTERFACE IN FIFTH EMBODIMENT-   209 BLOCK START NOTIFICATION UNIT IN SEVENTH EMBODIMENT-   210 BLOCK STOP NOTIFICATION UNIT IN SEVENTH EMBODIMENT-   300 MOBILE TERMINAL-   400 SUBSCRIBER SERVER-   500 POLICY DETERMINATION NODE-   501 TERMINAL SITUATION RECOGNITION UNIT-   502 POLICY DETERMINATION UNIT-   503 POLICY NOTIFICATION UNIT

1. A method performed by a mobility management node, the mobilitymanagement node arranged in a core network, the method comprising:determining a parameter which indicates a time interval based oninformation about a behavior of the mobile terminal; and notifying aradio access network node of the parameter, wherein control related tostate-transition of the mobile terminal is performed by the radio accessnetwork node using the parameter.
 2. The method according to claim 1,wherein the parameter is used by the radio base station to reduce statetransitions of the mobile terminal between a CONNECTED state and an IDLEstate.
 3. The method according to claim 1, wherein the notifyingcomprises notifying the radio access network node of the parameterduring setup of S1 signaling connection.
 4. The method according toclaim 1, wherein the parameter relates to state-transition of the mobileterminal between ECM-CONNECTED and ECM-IDLE states.
 5. The methodaccording to claim 1, wherein the parameter is determined based onsubscription information.
 6. The method according to claim 1, whereinthe parameter relates to state-transition of the mobile terminal inwhich the state from a CONNECTED state to an IDLE state is changed by anS1 release procedure.
 7. The method according to claim 1, wherein theparameter relates to state-transition of the mobile terminal in whichthe state from an IDLE state to a CONNECTED state is changed by aService Request message.
 8. The method according to claim 1, wherein theparameter relates to state-transition of the mobile terminal in whichthe state from a CONNECTED state to an IDLE state is changed by aprocedure in which a message is sent by the mobility management node. 9.The method according to claim 1, wherein the parameter relates tostate-transition of the mobile terminal in which the state from an IDLEstate to a CONNECTED state is caused by a procedure in which a messageis sent between the mobile terminal and the mobility management node.10. A method performed by a radio access network node, the methodcomprising: communicating with a mobility management node which isarranged in a core network; and performing control related tostate-transition of a mobile terminal using a parameter of which theradio access network node has been notified by the mobility managementnode, the parameter indicating a time interval, wherein the parameter isdetermined by the mobility management node based on information about abehavior of the mobile terminal.
 11. The method according to claim 10,wherein the parameter is used to reduce state transitions of the mobileterminal between a CONNECTED state and an IDLE state.
 12. The methodaccording to claim 10, wherein the radio access network node is notifiedof the parameter by the mobility management node during setup of S1signaling connection.
 13. The method according to claim 10, wherein theparameter relates to state transition of the mobile terminal betweenECM-CONNECTED and ECM-IDLE states.
 14. The method according to claim 10,wherein the parameter is determined based on subscription information.15. The method according to claim 10, wherein the parameter relates tostate-transition of the mobile terminal in which the state from aCONNECTED state to an IDLE state is changed by an S1 release procedure.16. The method according to claim 10, wherein the parameter relates tostate-transition of the mobile terminal in which the state from an IDLEstate to a CONNECTED state is changed by a Service Request message. 17.The method according to claim 10, wherein the parameter relates tostate-transition of the mobile terminal in which the state from aCONNECTED state to an IDLE state is changed by a procedure in which amessage is sent by the mobility management node.
 18. The methodaccording to claim 10, wherein the parameter relates to state-transitionof the mobile terminal in which the state from an IDLE state to aCONNECTED state is caused by a procedure in which a message is sentbetween the mobile terminal and the mobility management node.
 19. Amethod performed by a mobile terminal, the method comprising:communicating with a radio access network node; and being controlled ofa state transition by the radio access network node using a parameter ofwhich the radio access network node has been notified by a mobilitymanagement node arranged in a core network, the parameter indicating atime interval, wherein the parameter is determined by the mobilitymanagement node based on information about a behavior of the mobileterminal.
 20. The method according to claim 19, wherein the parameter isused to reduce state transitions of the mobile terminal between aCONNECTED state and an IDLE state.